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arXiv · 2311.09043

Measurement-induced transitions beyond Gaussianity: a single particle description

Luca Lumia·Emanuele Tirrito·Rosario Fazio·Mario Collura
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Abstract

Repeated measurements can induce entanglement phase transitions in the dynamics of quantum systems. Interacting models, both chaotic and integrable, generically show a stable volume-law entangled phase at low measurement rates which disappears for free, Gaussian fermions. Interactions break the Gaussianity of a dynamical map in its unitary part, but non-Gaussianity can be introduced through measurements as well. By comparing the entanglement and non-Gaussianity structure of different protocols, we propose a new single-particle indicator of the measurement-induced phase transition and we use it to argue in favour of the stability of the transition when non-Gaussianity is purely provided by measurements

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Luca Lumia, Emanuele Tirrito, Rosario Fazio, Mario Collura. 2023-11-15. Measurement-induced transitions beyond Gaussianity: a single particle description. https://doi.org/10.1103/physrevresearch.6.023176

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